1. Field of the Invention
The present invention relates to a transformer, and in particular to a transformer having assembled bobbins and a voltage transformation module having the transformer.
2. Description of Prior Art
A transformer is an electronic component in which magnetic cores, primary windings and secondary windings are provided to generate electromagnetic induction for converting voltage. The conventional transformer includes a bobbin and two magnetic cores. The bobbin is formed into a hollow cylindrical shape and has an axial channel. Both ends of the bobbin extend to form a plurality of pins. Two sets of electric leads are wound around both ends of the bobbin adjacent to its corresponding pin in different turn numbers, thereby forming a primary winding and a secondary winding respectively. Then, the two magnetic cores are disposed on both ends of the bobbin respectively.
However, since the interior of the bobbin of the conventional transformer is an axial channel, an electric current or an induced current flowing the electric leads inevitably generates heat, and the heat will be accumulated inside the bobbin (i.e. in the axial channel). Such a problem of heat accumulation is more serious in a large-power transformer such as a 600-watt transformer. Since the conventional transformer is not provided with any heat-dissipating means, the heat accumulated inside the bobbin will cause the increase in its temperature after being operated for a period of time. Even, the performance of the transformer may be deteriorated by the rising temperature. A conventional solution is to mount a heat-dissipating fan outside the bobbin. However, both ends of the bobbin are blocked by the magnetic cores, so that the airflow generated by such an external fan can only blow the outer surface of the bobbin, but cannot dissipate the heat accumulated inside the bobbin. As a result, the temperature of the conventional transformer still rises after being operated for a period of time.
In addition to the issue of heat dissipation, the bobbin of the conventional transformer is integrally formed into one body. Thus, if the transformers of different sizes are to be manufactured, the manufacturer has to produce various bobbins of different sizes and respective casings corresponding to the various bobbins. As a result, the manufacturer has to spend a lot of money to design various molds for this purpose, which increases the production cost. Thus, the manufacturer proposes a transformer having combined bobbins, in which a plurality of bobbins is combined with each other. These bobbins are combined with or adhered to each other to thereby forming a bobbin assembly. However, such a conventional transformer having combined bobbins does not solve the problem of heat accumulation in the bobbin.
Therefore, it is an important issue for the present Inventor to solve the above-mentioned problems.